Are those bugs reflective? Non-destructive biofilm imaging with white light interferometry
White light interferometry (WLI) is not typically used to image bacterial biofilms that are immersed in water because there is insufficient refractive index contrast to induce reflection from the biofilm’s interface. The soft structure and water-like bulk properties of hydrated biofilms make them difficult to characterize in situ by any means, especially in a non-destructive manner. Here we describe a new method for measuring and monitoring the thickness and topology of live biofilms using a WLI microscope. A microfluidic system was used to create a reflective interface on the surface of biofilms. Live biofilm samples were monitored non-destructively over time. The method enables surface metrology measurements (roughness, surface area) and a novel approach to measuring thickness of the thin hydrated biofilms. Increase in surface roughness preceded observable increase in biofilm thickness, indicating that this measure may be used to predict future development of biofilms. We have also developed a flow cell that enables WLI biofilm imaging in a dynamic environment. We have used this flow cell to observe changes in biofilm structure in response to changes in environmental conditions - flow velocity, availability of nutrients, and presence of biocides.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 1339040
- Report Number(s):
- PNNL-SA-119531
- Resource Relation:
- Conference: Interferometry XVIII, August 28, 2106, San Diego, California. Proceedings of SPIE, 9960:Paper No. 996004
- Country of Publication:
- United States
- Language:
- English
Similar Records
Monitoring bacterial biofilms with a microfluidic flow chip designed for imaging with white-light interferometry
In situ non-destructive measurement of biofilm thickness and topology in an interferometric optical microscope